Today is our review day as we will have the midterm exam next week.

First, we went over the making square part (Ch 12.4) that the substitute teacher did not get to finish last week. In particular, we talked about how to derive the general formulae for solving a generic quadratic equation ax^2 + bx +c. I hope every student really understands this.

Some students missed last week’s homework because they didn’t see it in my last post (I posted two articles last week, the first one with homework, the second one didn’t). If so, please get it this week and do it. It will help you prepare for the midterm exam.

We then went over what we learned so far this semester, mainly Chapter 10 and 11, plus 12.4 (making squares).

For homework, please do the Chapter 11 standarized test in the book. This is to help you prepare. You should also look back to Chapter 10’s test to help you review as well.

Sorry that I miss the school today due to Lexington Town business.

The material covered today are the following:

Ch 11.7 on dividing polynomials; Ch 11.8 on rational equations.

It is important to remember that when solving rational equation, always check your answer and throw away any that makes any denominator zero.

We also cover Ch 12.4 on conpleting squares. This is to let students learn how to derive the general solution for a quadratic equation of ax^2 + bx + c = 0

For homework, visit the link below:

http://blog.newtonchineseschool.org/wangweidong/files/2012/03/Math7_Spring_HW_L6.pdf

We started the topic of rational expression operation today. A rational expression is a fraction with either numerator or denominator or both being a polynomial. As such, all rules for dealing with factions apply.

A rational expression is simplified if there is no common factor between the numerator and denominator (other than 1 or -1).

We covered rational expression multiplication and division, followed by addition and substraction. The goal is to reach a rational expression in its simplified form after the operation.

Homework link can be found with the link below:

http://blog.newtonchineseschool.org/wangweidong/files/2012/03/Math7_Spring_HW_L5.pdf

Sorry I could not go to school to teach today, as I had two important campaign events to go to.

As some of you know, I am running for Lexington Housing Authority and Town Meeting Member this time and the election day is coming Tuesday 3/6. This weekend is the last weenend before the election.

So, if you are a Lexington resident, I hope you will go out to vote on Tuesday and vote for me.

That said, here is the material covered today by a substitute teacher:

Section 11.1 on Ratio and Propertion, two important properties to remember:

1. Reciprocal Property: if a/b = c/d, then b/a = d/c if they exist

2. Cross Product Property: if a/b = c/d, then ad = bc

Section 11.2 on Percents: number being compared to base = percent of base number

Section 11.3 on Direct and Inverse Variation:

The variables x and y vary directly if for a constant k, y/x = k or y = kx, k not equal to 0.

The variables x and y vary inversely if for a constant k, xy = k, or y = k/x, k not euqal to 0.

Here is the homework:

http://blog.newtonchineseschool.org/wangweidong/files/2012/03/Math7_Spring_HW_L4.pdf